In existing wireless communications standards such as the 3rd Generation Partnership Project (The 3rd Generation Partnership Project, 3GPP) Long Term Evolution (Long Term Evolution, LTE), a network side broadcasts a system bandwidth, namely, a spectrum resource, used by a current cell; and a piece of user equipment (User Equipment, UE) communicates with the network side within the notified system bandwidth.
Specifically, from establishment of a radio resource control (Radio Resource Control, RRC) protocol link to actual service transmission, all spectrum resources, of the UE, used for data receiving and transmission are limited within the system bandwidth broadcast by a system, and these spectrum resources need to satisfy a limited number of standard bandwidth values that are defined by a standard. In addition, to implement downlink dynamic adaptation, the UE needs to measure downlink reference signals, and feeds back a measurement result to the network side, where these downlink reference signals for measuring channel state information are all transmitted based on a limited number of standard bandwidths, and a measurement manner used on the side of the UE is also based on the several standard bandwidths.
However, an actual available bandwidth is different from the system bandwidth to some extent in an actual situation. For example, in many scenarios such as frequency-division multiplexing (Frequency-division multiplexing, FDM) inter-cell interference coordination (Inter-Cell Interference Coordination, ICIC), a non-standard spectrum, and a capability difference between UEs, there is a case in which an actual available bandwidth is inconsistent with the system bandwidth.
The configuration manner in the prior art in which the network side limits all working spectrums of the UE within the system bandwidth cannot effectively and fully use a radio resource.